Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/708

646 of Engineering. A bore of 19 inches diameter was carried down to a depth of 1570 feet in about two and a half years (1864-7), for the purpose of obtaining a water supply for the sugar refinery of M. Say in Paris ; and the same engineer who executed this work (M. Dm), began in 1866 an Artesian boring of the huge diameter of 6J feet at the part of Paris named Suite aux Cailles, to be carried down to a depth of 2600 to 2900 feet. (See Engineering, vol. iii. p. 605.) Besides these monster wells, there are in the Paris basin a great many others, varying from 300 to 400 feet in depth, and from 2 to 8 inches in the diameter of the bore-hole. The Tertiary chalk strata over which London stands have been riddled with Artesian borings for the sake of pure water supply. The source of the New River (which was opened in 1613) is one of the chalk springs, at Chadwell, near Ware ; this alone yields London a twenty-fourth part of its water supply, some 4 Jr million gallons a day. Many of the large London breweries obtain the water employed in the manufacture of their beer from Artesian wells over 300 feet deep. The Kentish Town water-works have a well 900 feet deep, which penetrates the chalk bed some 580 feet. Arte sian wells also supply water to the Bank of England, the fountains at Trafalgar Square, the Mint, Pentonville Prison, Colney Hatch Asylum, Shoreditch Workhouse, the North Western Railway Station, Holloway Prison, &c. On the duke of Northumberland s property at Sion House there is a chalk well which descends 620 feet, and spouts the water up about 4 feet above the surface. At Merton in Surrey, at Brighton, at Southampton, all along the east coast of Lincolnshire, and in the low district between the chalk wolds near Louth and the Wash, Artesian borings have long been known, and go by the name of Uow-ivdls among the people of the district. It is worthy of notice that the general level to which the water rises in the London district has been very sensibly lowered by the immense number of perforations that have been made ; and in several wells where the water formerly rose to the surface, it now stands considerably below it, and requires to be pumped up. None of the Artesian borings in England approach the depths frequent on the Continent and in America. The average depth of the water-bearing stratum around Paris is six times that of the London chalk beds ; and in some parts of Germany and of America, wells have been sunk to even double the depth of the Parisian wells of Crenelle and Passy. At Chicago there are two wells, one 700 feet and the other 1000 feet deep, with a diameter of 5 inches, which supply the city with 800,000 gallons of water daily. At the town of St Louis, in the State of Missouri, an Artesian boring was carried down for 3147 feet, but as only brine was obtained, it was ordered by Government to be stopped in September 1868, when the depth was approach ing three-quarters of a mile. The deepest boring in the world is at Sperenberg, twenty miles from Berlin, having been sunk for the purpose of obtaining a supply of rock salt. A bore-hole of 16 feet diameter was carried down to the depth of 280 feet, where the salt bed began ; after a further descent of 680 feet was attained, the bore was reduced to 13 inches diameter, and then continued till the extraordinary depth of 4194 feet was reached, without having pierced through the salt deposit, which has thus the enormous thickness of at least 3907 feet. The following are some of the other most important Artesian sinkings that have been made. At Louisville, in Kentucky, a bore of 3 inches was carried to a depth of 2086 feet between April 1857 and the summer of 1858, when a supply of water almost as plentiful as that of Crenelle was obtained. At Charleston, South Carolina, there is a well 1250 feet deep, which was begun in 1848, and which discharges water some 10 feet above the surface at the rate of 1200 gallons an hour. In 1858 a well at Neusalwerk, near Minclen, had reached the depth of 2288 feet. At Bourne, Lincolnshire, there is a well 95 feet deep, which yields over half a million gallons of water per clay, the pressure being sufficient to supply the town and force the water to the tops of the highest houses. There is one, on the property of the Continental Hotel, in Philadelphia, over 200 feet deep, and 8 inches in diameter, which yields 50,000 gallons a day. Two Artesian wells at Croydon supply a million gallons of water per day ; and Brighton draws over a million gallons from Artesian sinkings. There is a well at Bages, near Perpignan, which gives 330 gal lons per minute ; and one at Tours, which jets about 6 feet above ground, and gives 237 gallons per minute. The boring of wells in the great desert of Sahara is a very ancient industry ; and some oases are supplied with water wholly from Artesian wells. The average depth of these is from 100 to 200 feet, and the upper strata have only to be pierced to give a constant stream. With their primitive methods of boring, the Arabs often labour for years before they reach the wished-for pool ; and with only palm wood as a casing, they have great difficulty in keeping the bore-hole from closing up by the drifting of the sand, and they require to scour them out periodically. Since 1858 an immense number of perforations have been made by French engineers, and the fertilising effect upon the sandy desert plains is already making itself apparent. Villages are built and palm trees are growing where for merly there was but waste and solitude. (See Geological Magazine, vol. i. p. 31.) The importance of deep wells in such cases cannot be over-estimated. Artesian wells have been made to supply warm water, for keeping hospitals, &c., at a constant temperature. In variably the temperature of water from great depths is higher than that at the surface, this being due to some unknown source of heat in the interior of the globe. The tempera ture of the water in the well at Grenelle is 82 Fahr., and that of Passy the same, showing that they have a common source. Kissingen well has a temperature of 66 Fahr., that of St Louis one of 73 4 Fahr., that of Louisville 76^ Fahr., and that of Charleston 87 Fahr. The average rate of increase of temperature is 1 for a descent of from 40 to 55 feet. In Wiirtemberg the water of Artesian wells is employed to maintain in large manu factories a constant temperature of 47 when it is freezing outside. Artesian waters have also been employed to reduce the extreme variations of cold in fish-ponds, which are so fatal to their finny inhabitants. 1em  ARTEVELDE,, a celebrated Flemish popular leader in the 14th century, was a brewer in Ghent. His enormous wealth, great eloquence, and general talent for administration, easily made him the most prominent and powerful man on the side of the citizens in their struggle against the encroachments of Count Louis of Flanders. The people of Ghent gave him the command of their forces, and he banished from the town all the nobles and adher ents of the count. In 1335 he made a commercial treaty with Edward III. of England, and with the aid of some English troops expelled Louis from Flanders. Ten years later, in 1345, after having persuaded Edward to assume the title of king of France, and induced the Flemings to